TY - JOUR
T1 - Two-dimensional nickel hydroxide nanosheets with high-content of nickel(III) species towards superior urea electro-oxidation
AU - Wang, Dongsheng
AU - Liu, Siwen
AU - Gan, Qiuping
AU - Tian, Jianniao
AU - Isimjan, Tayirjan Taylor
AU - Yang, Xiulin
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/11/15
Y1 - 2018/11/15
N2 - Development of high-efficient and stable electrocatalysts for urea oxidation reaction (UOR) is of a great challenge due to the sluggish kinetics of 6e− transfer process. Here, we have developed a facile and easy-to-scale approach to fabricate two-dimensional Ni(III)-rich Ni(OH)2 nanosheets on amine-functionalized carbon (Ni3+-rich Ni(OH)2/C-NH2). Morphological characterizations confirm the existence of nanosheets, and XPS spectra indicate that the content of Ni3+ species in Ni3+-rich Ni(OH)2/C-NH2 (ca. 57.6%) is significantly higher than that of in Ni(OH)2/C-NH2 (ca. 43.1%) and Ni(OH)2/C (ca. 20.7%). Electrochemical analyses illustrate that the as-prepared Ni3+-rich Ni(OH)2/C-NH2 catalyst exhibits the highest current density (91.72 mA cm−2) at a potential of 0.61 V, which is 2.06-, 2.08- and 3.47-fold higher than that of Ni(OH)2/C-NH2, Ni(OH)2/C and Pt/C, respectively. Moreover, the Ni3+-rich Ni(OH)2/C-NH2 catalyst also demonstrates an outstanding voltammetric cycles and long-term chronoamperometric stability. The superior electrocatalytic activity and stability could be ascribed to the synergistic effect of Ni3+ doping as well as the amine-functionalized carbon, where higher concentration Ni3+ species in Ni(OH)2 sheets could provide more active sites for adsorption and transformation of urea molecules, while fluffy C-NH2 support could enhance the ability of solute diffusion, electron transport and gas emissions, thereby dramatically improve the catalytic activity.
AB - Development of high-efficient and stable electrocatalysts for urea oxidation reaction (UOR) is of a great challenge due to the sluggish kinetics of 6e− transfer process. Here, we have developed a facile and easy-to-scale approach to fabricate two-dimensional Ni(III)-rich Ni(OH)2 nanosheets on amine-functionalized carbon (Ni3+-rich Ni(OH)2/C-NH2). Morphological characterizations confirm the existence of nanosheets, and XPS spectra indicate that the content of Ni3+ species in Ni3+-rich Ni(OH)2/C-NH2 (ca. 57.6%) is significantly higher than that of in Ni(OH)2/C-NH2 (ca. 43.1%) and Ni(OH)2/C (ca. 20.7%). Electrochemical analyses illustrate that the as-prepared Ni3+-rich Ni(OH)2/C-NH2 catalyst exhibits the highest current density (91.72 mA cm−2) at a potential of 0.61 V, which is 2.06-, 2.08- and 3.47-fold higher than that of Ni(OH)2/C-NH2, Ni(OH)2/C and Pt/C, respectively. Moreover, the Ni3+-rich Ni(OH)2/C-NH2 catalyst also demonstrates an outstanding voltammetric cycles and long-term chronoamperometric stability. The superior electrocatalytic activity and stability could be ascribed to the synergistic effect of Ni3+ doping as well as the amine-functionalized carbon, where higher concentration Ni3+ species in Ni(OH)2 sheets could provide more active sites for adsorption and transformation of urea molecules, while fluffy C-NH2 support could enhance the ability of solute diffusion, electron transport and gas emissions, thereby dramatically improve the catalytic activity.
KW - Electrocatalysis
KW - Ni(III) rich
KW - Ni(OH) sheets
KW - Two-dimensional
KW - Urea electro-oxidation
UR - http://www.scopus.com/inward/record.url?scp=85054459373&partnerID=8YFLogxK
U2 - 10.1016/j.jelechem.2018.10.007
DO - 10.1016/j.jelechem.2018.10.007
M3 - Article
AN - SCOPUS:85054459373
SN - 1572-6657
VL - 829
SP - 81
EP - 87
JO - Journal of Electroanalytical Chemistry
JF - Journal of Electroanalytical Chemistry
ER -